use warnings;
use strict;

my $good_orgs = "First\nNational\nBank\nCompany\nLLC\nlegal";
my %good_orgs = map {lc()=>1} split /\n/, $good_orgs;
sub is_good_org {
	my $organization = shift;
	my @parts = grep {length} split /[\s;,]+/, $organization;
	for my $org (@parts) {
		return unless exists $good_orgs{lc $org};
	}
	return 1;
}

print is_good_org("LLC")            ?"yes":"no", "\n"; # "yes"
print is_good_org("Company, LLC")   ?"yes":"no", "\n"; # "yes"
print is_good_org("National Bank")  ?"yes":"no", "\n"; # "yes"
print is_good_org("legal company")  ?"yes":"no", "\n"; # "yes"
print is_good_org("National Bunk")  ?"yes":"no", "\n"; # "no"
print is_good_org("Illegal Exports")?"yes":"no", "\n"; # "no"
print is_good_org("Test LLC")       ?"yes":"no", "\n"; # "no"